Process for producing soda containing water of crystallization or mixtures thereof with other substances



Patented Apr. 1,1924.

"res;

ADOLF WELTER, or KaErELD-BooKUnt, GERMANY.

TROCESS FO R PRODUCING SODA CONTAINING WATER OFCRYSTALLIZATION'OR MIX- TUBES THEREOF WITH OTHER SUBSTANCES.

1N0 Drawing. Application filed July 9,

To all whom it may concern: 7

Be it known that I, Dr. ADoLr XVELTER, citizen of the German Empire, residing at Krefeld-Bockum, Rhineland, Germany, have 6 invented new and useful Improvements in Processes for Producing Soda Containing "Water of Crystallization or Mixtures Thereof with Other Substances, of which the following is a specification. My invention relates to processes formanufacturing hydrated sodium carbonate and mixtures of same with substances soluble in water, a-ndit particularly relates to those processes by which a saturated aqueous solu- 1 tion of soda is sprayed into the air, the object of the invention being to render the process more expeditious and to produce the hydrated soda and other products at lower cost. My new invention consists in spraying 2 water divided into as fine particles as possible unto commercial pulverized calcined soda Na CO and inpreventing same from lumping and caking by a suitable treatmentand arrangement of the apparatus employed) 2 If, instead of of pure water, solutions or alkali metal salts, preferably sodium salts, as for instance water-glass, Glaubers salt or soap are sprayed onto the soda, corresponding mixtures of soda and the particular substances used will be obtained. Of course, other salts than that of Glauber may also be added'itothe soda to be treated. It will be apparent from the above that the process employed may consist in blowing steam, or water divided into very fine particles, into a sort of tower, and in causing calcined soda, which has been finely sifted or reduced to fine powder, by compressed air to drop from above through'the water vapor, while cold 46 air is blown in from below. The air may be cooled expressly for this purpose. Under certain conditions snow may be advantageously used instead of water. According to the size of the tower as well as to thequantity of the air that is introduced from below for the purpose of cooling the soda the temperature of which* tends to rise, and according to the time within which the various substances mentioned above react upon each 60 other more or less non-caking refined soda containing water of crystallization is obtained at the bottom of the tower, which may be sold without furtherpulverization.

A..modified process consists in transfo'rmv M ing a jet of water into a fine spray by blow- 1920. Serial no. 395,076.

and containing about 5055% of anhydrous carbonate of soda is obtained.

In another modified process a thin layer I ofcalcined soda is placed upon a long conveyor belt, or a worm or the like, and caused to brush past small resisting members that a keep the soda continuously moving. By now spraying athin aqueous solution of waterglass through suitable nozzles unto the conveyor belt, and by adjusting the speed of the travelling belt on'theone hand and the spraying nozzle on the other, a continu ously working process may be obtained by which a finely pulverized washing powder is produced which does not cake and which is also immediately marketable without further pulverization. The length of the con veyor belt or the like depends upon the quantity of water that is to be absorbed and this quantity is so adjusted that with the average humidity of the air a state of equilibrium is obtained, the gain or loss of weight in the finished product that is due. tothe varying humidity of the air is then not appreciable. A further modified process consists in keeping pulverized calcined soda continuously moving in a. suitable mixing vessel and in spraying 'an aqueous soap solution, which should be as finely divided as possible, unto the soda; The spray of the solution is regulated in such a manner as to prevent the soda from heating enough to cause caking or liquefaction. The. quantity of the charge in the apparatus must therefore always be in a proper proportion to the cooling surface, and this proportion is afiected very considerably by the temperature of the surrounding air. It is a matter of course that'any one of the processes hereinbefore described may be employed according to-circumstances. The essential features of the invention are, that the calcined soda shall be divided into fine particles, thatit shall be subject to the action of fine particles of water (liquid, vapor or snow), that suitable means (such as low temperature, or stirring, or both) shall be provided to prevent liquefaction or caking of the product, and finally that, if desired,

any suitable substances may be added to the mixture thus produced Whilst the described process is being carried out. The process is very simple and easy to employ and offers considerable technical and economical advantages over known processes for producing powdered crystal soda or mixtures thereof.

1 claim:

1. A process for manufacturing hydrated sodium carbonate in the form of a fine crystalline powder, consisting in acting upon fine particles of anhydrous sodium carbonate With Water in the form of a fine spray and keeping the sodium carbonate in motion during the reaction. v

2. A process for manufacturing hydrated sodium carbonate in the. form of a fine crystalline powder, consisting in acting upon fine particles of anhydrous sodium carbonate with Water in the form of a fine spray and keeping the sodium carbonate at a low temperature during the reaction.

3. A process for manufacturing hydrated sodium carbonate in the form of a fine crystalline powder, consisting in acting upon fine particles of anhydrous sodium carbonate With Water in the form o l a fine spray and ,esenee keeping the sodium carbonate at a low temperature and in motion during the reaction.

l. process for manufacturing a fine crystalline powder of a. mixture or sodium carbonate and an alkali metal salt, said process consisting in acting upon fine particles of anhydrous sodium carbonate with an aque one solution of an alkali-metal salt sprayed upon the sodium carbonate and blowing a current of air against the sodium carbonate Whilebeing thus treated.

5. A process for manufacturing a fine crystalline powder of a mixture of sodium carbonate and of soap, said process consisting in acting upon fine particles of anhydrous sodium carbonate with, an aqueous solution of soap sprayed upon the sodium carbonate, and blowing a current of air against the sodium carbonate While being thus treated.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

-DR. ADOLF WELTER. Witnesses:

KARL ALBER'rs, PETER Munsnnr. 

